private function formatIndexNumber(item:Object, colum:Object):String {

      return indexNumLabelFun(item, colum.mx_internal::owner);

  }

 

public function indexNumLabelFun(value:Object, dataGrid:Object):String {

     var arr:Array = (PageDataGrid.dataProvider as ArrayCollection).toArray();

     var indexNum: int = (arr.indexOf(value) + 1);   

     Alert.show(indexNum.toString(), "prompt");

     data.abc = indexNum.toString();    

     return indexNum.toString();

}

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<mx:DataGridColumn  headerText="序号" width="60" editable="false">

     <mx:itemRenderer>

      <mx:Component>

       <mx:Button label="{this.parentDocument.genrowno(data)}" height="18" cornerRadius="1"/>

      </mx:Component>

     </mx:itemRenderer>

   </mx:DataGridColumn>

public function genrowno(ob:Object):String {

  return String(PageDataGrid.dataProvider.getItemIndex(ob) + 1);  

 }

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private function formatIndexNumber(item:Object, colum:Object):String {     return indexNumLabelFun(item, colum.mx_internal::owner); } public static function indexNumLabelFun(value:Object, dataGrid:Object):String {    var arr: Array = dataGrid.dataProvider.source;    var indexNum: int = (arr.indexOf(value) + 1);                return indexNum.toString(); }
     

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user = new User(); user.id = i; user.username = "abc" + i; user.password = "efg" + i; ar.addItem(user); } this.dg.dataProvider = ar; } ]]>